Automake includes support for automatic generation of cscope and ctags targets. Now, theoretically, you can take any open-source project which uses GNU build system (and manyyy of them do) and type "make cscopelist" or "make ctags" or "make tags" and it will automatically generate the tags! Not that generating tags was a very difficult process earlier, but with support in automake, we can tinker around with the tags a lot.
Eg. If there is an arch/ subdirectory in your source-code and you don't want your cscope tags to be polluted by the IA64 code that you don't really care about, you can do it very easily by modifying the Makefile.am file in the arch directory.
I.e. you can easily control how your tags are generated!
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